1. Field of the Invention
The present invention relates to improvements in tile cutters generally and namely to devices for scoring and fracturing tile, glass and the like ceramic or vitreous plate-like materials. More particularly it relates to an improved and simplified device for scoring and fracturing ceramic tile and includes a novel means to position the tile for precise cuts, both perpendicular to and diagonally to the referenced edge.
2. Description of the Prior Art
The literature is replete with descriptions of numerous prior art devices which have been designed to accomplish the dual task of both scoring or incising and subsequently fracturing a ceramic tile, plate of glass or a like vitreous material. Most of the prior art devices have suffered from minor drawbacks which have not proved critical until recently. Recent developments which have led to the development of improved tile cutters are the increasing hardness of ceramic tiles as ceramic technology improves; the increasing thickness of ceramic tiles in use today for decorative effects; and the pressure for greater productivity of the tile installer because of rising labor costs.
Until recently, the only commercially available and widely used tile cutters were one sold under the tradename Simplex and disclosed in U.S. Pat. No. 1,873,721 and others issued to Postley; and one sold under the tradename Tilex and disclosed in U.S. Pat. No. 2,246,351 and others issued to Engleke. Both of these tile cutters suffered from the fact that the tile was placed in one position for scoring or incising and then placed in another position for fracturing. While not necessarily a difficult operation, this extra motion was ineffecient in its consumption of time. It also required extra manipulation of the component assemblies of the tile cutters. A second consideration leading to the development of new tile cutters is that neither of these commercially available tile cutters performs well with the very thick tiles which are now both available and extremely popular in the consumer market.
Recently, an improved tile cutter, made under U.S. Pat. No. 4,026,262, issued to Yasuga, has become commercially available. This tile cutter is very similar to that of the present invention, but also differs from the present invention in critical respects. Both the Yasuga device and the device of the present application are attempts to improve and simplify the Tilex device and both use variations of the Simplex handle. Both devices use a guide rod positioned above and parallel to the cutter base. Both use a curved handle bearing a cutting wheel or disk which scores a tile when pressure is applied to the handle and the handle is pushed along the guide rod under pressure. These features are old and are disclosed in the Postley and Engleke patents. Both the Yasuga device and the device of the present invention improve upon the prior art in the neither device requires repositioning of the tile in order to fracture the tile along the scored line. Each of these devices accomplishes this goal by incorporating a pair of lateral fins at the base of the curved handle some distance behind the scoring desk. After the tile is scored, additional downward pressure is exerted upon the handle, causing the fins to engage the tile and forcing a fracture along the scored line. The combined handle, scoring desk and fin structure of the Yasuga device and the device of the present invention are different. The Yasuga handle incorporates and claims a complex cam means for adjustment of the height of the scoring desk for varying thicknesses of tile. This requires additional time and work for the laborer and serves no useful purpose. With applicant's device, which has a simple, fixed position cutting disk, the user simply raises or lowers the handle to accomodate tiles of varying thickness. The height adjustment means for the scoring desk as implemented and claimed in the Yasuga device are simply unnecessary complexities which have no effect on the functional performance of the device. Applicant's handle means is simpler in structure, has fewer parts, is less expensive to manufacture, is simpler to use and is at least equally effective. It should be pointed out here that the Yasuga device has been commercially available for about one year at the time of this writing while applicant's device has just finished its prototype development. For reasons which are not at all obvious and in fact are unknown to the trade, the Yasuga device does not function well in the cutting of thick, hard tiles. For this reason and for another reason, discussed hereinafter, the Yasuga device has been a commercial failure in the trade.
The Yasuga device uses and claims an adjustable sliding plate means mounted within the handle to facilitate the sliding movement of the handle along the guide rod. This is not only unnecessary; it also adds to the cost and complexity of the device.
The most notable deficiency in the Yasuga device, and the prime reason for its commercial failure, is its complex means for originally positioning the tile on the base of the tile cutter. Yasuga uses a graduated scale embossed on the base of the tile cutter and two bars on either side of the center line to engage the straight edges of the tile to hold it in position. Each of these two bars requires two screws to tighten it in position. Thus, to position a tile for a precise cut in the Yasuga device, four screws must be loosened, two bars moved, the tile must be positioned using the scale, the two bars must be repositioned to engage the edges of the tile and the four screws must be retightened. Both the device and the process are too complex and too time-consuming for the tile installer who is simply trying to move quickly to make a profit on the job. And despite the alleged precision attainable with the device of Yasuga, this device is not capable of positioning a tile for a precise diagonal cut.
The device of the present invention provides a simple means to make the usual straight cuts and also permits quick and precise diagonal cuts.
All tile cutters operate on the same basic principles. The tile is first scored and then pressure is applied on each side of the score to fracture the tile along the score. The ultimate design objective is to obtain as clean a break as possible, or a straight, flat edge along the fracture. A second design objective is to position the fracture as accurately as possible on the tile so that the resulting fractured tile fits precisely into the desired pattern of the finished work. A third design objective is to accomplish the two prior objectives as quickly as possible to save labor. A fourth design objective is to minimize the pressure required to fracture the tile to prevent marring of the tile surface. All of these design objectives are achieved by the improved simple structure of the tile cutter of the present invention.
The present invention uses a simple L-shaped bar held in position by only one screw to position a tile for an accurate cut. A notch in one leg of the L-shaped bar and an angle on the other leg permit diagonal cuts to be made with equal precision. While this might be suggested by the prior art, it is not disclosed therein and represents a significant improvement over the prior art including the recent Yasuga patent.